Characteristic Analysis of Japanese Cedar Powder from Vibration Mill with Ring Media Pulverization Using Solid State NMR

Abstract

We developed vibration mill with ring media as a highly efficient pretreatment technique to obtain monomeric sugar from biomass. The enzymatic digestibility of Japanese cedar powder was improved to 60% by vibration mill with ring media dry pulverization. However, improvement of enzymatic digestibility mechanism was not clarified because of pulverized powder agglomeration. This study investigated the structural change and domain size of a vibration milling with ring media pulverized Japanese cedar powder using solid state NMR. Results show that the between domain size of Japanese cedar powder decreased to 8 nm during 60 min pulverization. A relation was confirmed between domain size and enzymatic digestibility. The enzymatic digestibility was expected to improve by increase surface area through contact by cellulose enzymes. Furthermore, cellulose crystallinity remained almost natural. These results suggest that Japanese cedar powder from vibration milling with ring media can be used as a cellulose nanomaterial. Investigation using ICP-MS was applied to assess the noise of the NMR spectrum from the remnant carbon steel. Results showed no influence of any remnant carbon steel powder. This study clarified the improved enzymatic digestibility mechanism and demonstrated the possibility of cellulose nanomaterial production by dry pulverization.